Which of the following statements is correct for CO? 

• A

  A double bond between C and O atoms 

• B

  $1\sigma ,1\pi \text{ and }1\text{ coordinate bond between }\mathrm{C}\text{ and }\mathrm{O}\text{ atoms }$

• C

  One lone pair of electrons on each atom

• D

  $1\sigma ,2\pi \text{ bonds between }\mathrm{C}\text{ and }\mathrm{O}\text{ atoms }$